in ignorance but always trying to learn.....
I had win 7 OS on 3TB (Seagate disc wizard configured it) decided after six months too much info on one hard drive, too risky in case of drive errors or viruses...
I put the old drive back in (500GB) I had not formatted it so plug in and use...
on start up the 3TB over rides system and tries to open as main drive....it shows as disk 0 in computer management
if I unplug the sata lead the 500GB becomes disk 0
how can I get the 500GB to control start up? and become disc 0
I have run various tools to try and open or show the system partition and then delete it.
( disc wizard and dos and diskpart)
I then formatted it
the drive appears to be empty but it shows as 2.72TB
the drive still holds a boot record
can I factory reset the 3TB CC27 firmware (I have looked but cannot find a solution to this yet)
in bios the default boot is UEFI:Built-in EFI Shell
The 500GB lists as AHCI
THE 3GB lists as SATA
the desktop is usable with a F11 start up, but it takes a few attempts to get it running..
open to any ideas.....